a collage for charon

Basis for interactive sound installations involving smartphones and biosignals

Used in:

a collage for charon at A R E A Gallery's COLLAGE / Yi and the Thousand Moons OST release party, 12/1/2017
Praeludium at A R E A Gallery's POSSIBLE, 12/28/2017
Dance & Design Making Lab, MIT IAP workshop, 1/21/2018
Praeludium at Business for Peace's Climate Leadership Summit in Oslo, 5/15/2018 - 5/16/2018
... your next installation project :)

Dependencies

First, install:

Then, install all project dependencies:

# Python dependencies
pip install -r requirements.txt

# Node.js dependencies
npm install

Run the Node server, which receives data from the sensors via Bluetooth and sends it via WebSockets: node rfduino-js/index.js
- You should see "Node server started" in the terminal
- If you have devices streaming data, the data should pop up in the terminal as well
Run the Flask server, which receives data from the Node server and sends MIDI: python app.py
- You should see "Flask server started" in the terminal
- If you visit http://localhost:5000/biodance_conductor you should reach a page that displays Flex, BPM, and EDA on the right-hand side
Open morse Project/biomorse_native.als in Ableton
- If you visit http://localhost:5000/biodance_player and tap the blocks, you should hear notes triggered from Ableton. This is a useful way to test basic MIDI functionality
  - The way the "players" work is that each device gets assigned a different MIDI channel, which corresponds to one of the instruments in the Ableton project. For more details check out socket.on('my_response' in static/biodance_conductor.js

You can add/edit musical mappings in static/biodance_conductor.js. It uses the WebMidi.js (https://github.com/cotejp/webmidi) library to send MIDI.

On the biosignals side, if you take a look at socket.on('biosignal_data' in static/biodance_conductor.js (currently line 33 as of 1/13/2018), you'll see a bunch of midiOutput.sendControlChanges and midiOutput.playNotes. This is where everything happens; see the source or "Example mappings" below for more details.
IMPORTANT: You'll have to change the MIDI device name in order to get MIDI from the server to Ableton. Look for var midiOutputName = in static/biodance_conductor.js; as of 1/13/2018 it's currently set to "IAC Driver Bus 1" in line 237. Make sure that the name of midiOutputName matches the midi input device you're using in Ableton. On Macs you can go to Audio MIDI Setup to see available devices. You can also do:
```
for (var i=0; i < WebMidi.outputs.length; i++) {
    console.log(i + ": " + WebMidi.outputs[i].name);
}
```
in the JavaSript console to get a list of available MIDI outputs.

On the Ableton side, in order to map MIDI params you need to:

Go to Options > Edit MIDI Map (or Cmd+M)
Click the parameter in Ableton you want to map to, e.g. panning of an instrument. It should show up as subtly outlined in the UI.
Trigger the MIDI CC value or note.
- Since this can be annoying to trigger programmatically, for convenience there's a helper tool which you can access at http://localhost:5000/midi_mapping_helper. There you can enter a CC number / MIDI note, and then just press "trigger" to trigger it. This can save a lot of time!
- Alternately, if you have an actual MIDI controller you can just twiddle a knob/press a note to trigger it

As of 1/13/2018, the mappings between static/biodance_conductor.js and morse Project/biomorse_native.als are:

BPM (from HR biosignal) -> MIDI CC 1 -> Song Tempo
Flex biosignal -> MIDI CC 2 -> Drive parameter on Overdrive for Master channel
Flex biosignal -> MIDI CC 2 -> Drive parameter on Overdrive for "glass feedback" (channel 3)
Flex biosignal -> MIDI CC 2 -> Tone parameter on "genuine rhodes" (channel 1)
EDA biosignal -> MIDI CC 3 -> Dry/Wet parameter on Reverb for Master channel
EDA biosignal exceeds 500 -> trigger MIDI note B4 on channel 11
Heartbeat detected (from HR biosignal) -> trigger MIDI note C2 on channel 11